I totally get your point, man. Actually, Batman's a good example. Back in the 2000s, they actually did "kill" Bruce Wayne off for a time. There was even a whole Battle for the Cowl event which pitted a lot of characters trying to take up the mantle of Batman. I was totally fine with that, and a lot of characters brought a lot to the table. Eventually, the first Robin, Dick Grayson won and was Batman for quite some time. Since the other Robins already made their bid to become Batman, they wouldn't go back to being sidekicks. So, Damian Wayne, Bruce's son, became the new Boy Wonder. It really presented a new dynamic, and it gave the world a fresh Batman, who was unsure if he was suited for the role.

It's not just Batman, too. Bucky became Captain America for a while (which I was cool with), Jane Foster became Thor (which I'm still not cool with), the many Green Lanterns, Wally West became the Flash (which I grew up with), and many others. The point is, the same character doesn't need to live forever to become effective. Sometimes death, when meaningful, could have a better effect on a character's legacy than continuing on for decades.

I totally get your point though, thanks for sharing it! I appreciate it a lot :D